How Many Heads Do you Have?
Borrowing a joke (or a profundity?) from Bertrand Russell's Our Knowledge of the External World , I will now demonstrate that the reader has two heads. According to common sense, and the consensus of most (Occidental) philosophers, we exist "inside" an "objective universe," or -- to say otherwise -- the "objective universe" exists "outside" us. Very few people have ever doubted this. Those who have doubted it have arrived, inevitable, at highly eccentric conclusions.
Well, then, avoiding eccentricity and accepting the conventional view, how do we know anything about that "external universe?" How do we perceive it? (For convenience, I will consider only the sense of sight in what follows. The reader can check for himself, or herself, that the same logic applies if one changes the terms and substitutes hearing or any of our other senses.)
We see objects in the "external universe" through our eyes and then make pictures -- models -- of them in our brains. The brain "interprets" what the eye transmits as energy signals. (For now, we will ignore the data that shows that the brain makes a gamble that it can interpret these signals.) Again, very few Occidentals have doubted this, and those who have doubted it arrived at strange and incredible alternatives. So, then, we live "inside" an "external universe" and make a picture or model of it "inside" our brains, by adding together, or synthesising, and interpreting, our pictures or models of parts of the universe called "objects". Then, it follows that we never know the "external universe" and it "objects" at all. We Know the model of the "external universe" inside our brains, which exist inside our heads. In that case, everything we see, which we think of as existing externally, actually exists internally, inside our heads. But we have not arrived at solipsism, remember. We still assume the "external universe" from which we started. We have merely discovered that we cannot see it or know it. We see a model of it inside our heads, and in daily life forget this and act as if the model exists outside our heads -- i.e., as if (1) the model and the universe occupy the same area of space (as our map that tries show "all" about Dublin would occupy the same space as Dublin) and (2) this space exists "outside." But the model and the universe do not occupy the same space and the space where where the model exists can only be located "inside" our brains, which exists inside our heads.
We now realize that, while the universe exists outside, the model exists inside, and therefore occupies much, much less space than the universe. The "real universe" then exists "outside" but remains unexperienced, perhaps unknown. That which we do experience and know (or think we know) exists in local networks of electro-chemical bonds in our brains. Again, if the reader cares to challenge any part of this, he or she should try to imagine an alternative explanation of perception. It will appear, or has always appeared to date, that any and all such alternatives sound not only queerer than this but totally unbelievable to "people of common sense."
Well to proceed, we have now an "external universe," very large (comparatively speaking) and a model of same, much smaller (comparatively speaking), the former "outside" us and the latter "inside" us. Otherwise, I could not get up from my chair, walk to the door, go down the hall and accurately locate the kitchen and get another cup of coffee from something I identify as a Coffee Maker.
But where does our head exists? Well, our head obviously exists "inside" the "external universe" and "outside" our brain which contains the model of the "external universe." But since we never see or experience the "external universe" directly, and only see our model of it, we only perceive our heads as part of the model, which exists inside us. Certainly, our perceived head cannot exists apart from our perceived body as long as we remain alive, and our perceived body (including head) exists inside our perceived universe. Right?
Thus, the head we perceive exists inside some other head we do not, and cannot, perceive. The second head contains our model of the universe, our model of this galaxy, our model of this solar system, our model of Earth, our model of this continent, our model of this city, our model of our home,our model of ourselves and atop our model of ourselves a model of our head. The model of our head thus occupies much less space than our "real" head.
Think about it. Retire to your study, unplug the phone, lock the door and carefully examine each step of this argument in succession, noting what absurdities appear if you question any individual step and try an alternative.
Let us, for Jesus sake and for all our sakes, at least attempt to clarify hoe we can have two heads. Our perceived head exists as part (a very small part) of our model of the universe, which exists inside our brain. We have proven that, have we not? Our brain, however, however exists inside our second head -- our "real" head, which contains our whole model of the universe, including our perceived head.
In short, our perceived head exists inside our real head which exists inside the real universe.
Thus, we can name our two heads -- we have a "real" head outside the perceived universe and a "perceived head" inside the perceived universe, and our "real" head now appears, not only much bigger than our perceived head, but bigger than our perceived universe. And, since we cannot know or perceive the "real" universe directly, our "real" head appears bigger than the only universe we do know and perceive -- our perceived universe, inside our perceived head.
If you want to have your mind filled with more similar content (like Robest Antons text) try poking into the mind of Marcus at: 
Zyz (?), thanks for the link..interesting site. Maybe we can collaborate with them on this wiki? -Kunda